In accounting, the depreciation expense is used to allocate costs of long-lived assets in a rational, systematic pattern over the period the assets are expected to provide economic benefits. Therefore, in calculating operating results under . Generally Accepted Accounting Principles (GAAP) and International Financial Reporting Standards (IFRS), depreciation is a deduction in arriving at income before income taxes. Because it is a noncash deduction, in a cash flow statement prepared under financial accounting standards, depreciation is presented as an adjustment in reconciling net income to operating cash flow.
To what degree marijuana use is directly causal in these associations remains an open question requiring further research. It is possible that other factors independently predispose people to both marijuana use and various negative life outcomes such as school dropout. 58 That said, people report a perceived influence of their marijuana use on poor outcomes on a variety of life satisfaction and achievement measures. One study, for example, compared people involved with current and former long-term, heavy use of marijuana with a control group who reported smoking marijuana at least once in their lives but not more than 50 times. 59 All participants had similar education and income backgrounds, but significant differences were found in their educational attainment: Fewer of those who engaged in heavy cannabis use completed college, and more had yearly household incomes of less than $30,000. When asked how marijuana affected their cognitive abilities, career achievements, social lives, and physical and mental health, the majority of those who used heavily reported that marijuana had negative effects in all these areas of their lives.
The immediate effects of AAS in the brain are mediated by their binding to androgen (male sex hormone) and estrogen (female sex hormone) receptors on the surface of a cell. This AAS–receptor complex can then shuttle into the cell nucleus to influence patterns of gene expression. Because of this, the acute effects of AAS in the brain are substantially different from those of other drugs of abuse. The most important difference is that AAS are not euphorigenic, meaning they do not trigger rapid increases in the neurotransmitter dopamine , which is responsible for the “high” that often drives substance abuse behaviors. However, long-term use of AAS can eventually have an impact on some of the same brain pathways and chemicals—such as dopamine, serotonin, and opioid systems—that are affected by other drugs of abuse. Considering the combined effect of their complex direct and indirect actions, it is not surprising that AAS can affect mood and behavior in significant ways.